The invention relates to a method of examining an object by means of elastography, as well as to an arrangement for carrying out such a method and to a computer program for controlling such an arrangement.
The MR elastography (MR=Magnetic Resonance) method which is disclosed in U.S. Pat. No. 6,486,669 utilizes the fact that the phase in an MR image of the object changes under the influence of mechanical oscillations acting on the object. The extent of such a change is dependent on the excursion of the. tissue under the influence of the mechanical oscillations. Information concerning given mechanical parameters of the tissue can thus be derived from MR phase images, that is, images reproducing the phase of the nuclear magnetization; for example, such a parameters relates to the elasticity. In ultrasound elastography even direct measurement of the excursion is possible.
Malignant lesions such as, for example, a mastocarcinoma, clearly deviate in respect of elasticity from normal healthy tissue. However, there are also benign lesions which have similar elastic properties. Anomalous elastic properties, therefore, per se do not yet form an adequate indication that a tissue is malignant.